The present invention relates to a hydraulic construction for a working vehicle, for operating a hydraulic clutch mounted in a transmission case.
An oil passage for supplying oil to a rotary member such as a hydraulic clutch generally is defined axially of a rotary shaft connected to the rotary member. The oil is supplied to and drained from the oil passage thus defined, through a port defined adjacent an end of the rotary shaft.
However, the oil passage defined along the rotary shaft tends to be long and is difficult to cut and shape. It also has the disadvantage of an increased flow resistance. Particularly where a hydraulic clutch is operated by a hydraulic actuator, the increased flow resistance is deterimental to prompt clutch operation and causes delays or lags in the associated operation.